Various medical procedures require fluids to be delivered to specific locations within the body, typically via a fluid delivery catheter. A narrow steerable guidewire is often used to maneuver through narrow, tortuous, and/or branching body passageways. After the guidewire has been directed to the desired location, a fluid delivery catheter may be inserted over the guidewire. The guidewire is usually removed before fluid delivery begins. Guidewires which are themselves capable of fluid delivery (such as that disclosed in U.S. Pat. No. 5,322,508) are also known in the art.
During balloon angioplasty procedures, a catheter equipped with a small balloon is inserted (usually over a guidewire) into an artery that has been narrowed, typically by the accumulation of fatty deposits. The balloon is then inflated to clear the blockage or lesion and widen the artery. Upon balloon inflation, blood flow distal to (i.e., "downstream" from) the inflated balloon may be almost completely stopped.
Myocardial ischemia (i.e., a reduction in blood perfusion to the heart muscle) occurs transiently in the majority of patients undergoing coronary angioplasty procedures, such as balloon angioplasty, directional atherectomy, rotational atherectomy, and stent deployment. The permissible duration of occlusion due to balloon inflation or other device deployment is normally determined by the severity of myocardial ischemia. Typically, evidence of severe ischemia (including patient chest pain and ECG changes) requires that the operator deflate the balloon or remove the occlusive device after approximately 60 to 120 seconds. For anatomically difficult lesions, such as type B and C lesions, longer periods of balloon inflation (or other device deployment) are frequently desirable for the first balloon inflation or other device deployment.
Autoperfusion balloon catheters, and catheters of the type disclosed in U.S. Pat. No. 5,322,508, can in some circumstances allow longer periods of balloon inflation. However, the blood (or other physiologic liquid) flow through such devices is frequently insufficient to provide an adequate oxygen supply to tissues distal to the angioplasty balloon or other occlusive device.
Recent advances in the generation and application of oxygen supersaturated solutions have made it possible to deliver greater amounts of oxygen to tissues distal to an angioplasty balloon. U.S. Pat. No. 5,407,426, and pending application Ser. Nos. 08/273,652, filed Jul. 12, 1994, entitled "Method for Delivering a Gas-Supersaturated Fluid to a Gas-Depleted Site and Use Thereof"; 08/353,137, filed Dec. 9, 1994, entitled "Apparatus and Method of Delivery of Gas-Supersaturated Liquids"; 08/453,660, filed May 30, 1995, entitled "Method for Delivering a Gas-Supersaturated fluid to a Gas-Depleted Site and Use Thereof"; 08/465,425, filed Jun. 5, 1995, entitled "Method for Delivery of Gas-Supersaturated Liquids"; 08/484,279, filed Jun. 7, 1995, entitled "Apparatus and Method of Delivery of Oxygen-Supersaturated Physiologic Solutions During Clinical Procedures"; and 08/484,284, filed Jun. 7, 1995, entitled "High Pressure Gas Exchanger", which are incorporated herein by reference, disclose various methods for the generation and application of oxygen supersaturated liquids.
As is described in the above referenced patent applications, the generation, transport and delivery of oxygen supersaturated liquid may require the application of very high hydrostatic pressures. Accordingly, there remains a need for a high pressure fluid delivery device capable of infusing bubble-free fluid, which is supersaturated with oxygen, to vessels or ducts through and beyond the central lumen of a balloon angioplasty catheter or similarly occlusive device. There remains a further need for a quick connect/disconnect assembly which can withstand high pressures that may be experienced in delivering such oxygen supersaturated liquids from a fluid reservoir to a suitable fluid delivery device, and which can minimize the time required for the initiation or termination of oxygen supersaturated liquid perfusion.